While the types of cookware metals abound, Copper or Brass (an alloy of copper) stands out for being the finest practical conductor of heat which translates into low to moderate heat requirement to obtain the best results. It sure exceeds aluminum or stainless steel in heat conduction thus saving on precious and costly gas.
Brass being a soft material, a heavy hammering makes it stronger and able to withstand many more years of use than aluminum or steel cookware. It is also reactive to acidic foods, so it is usually lined with another metal, the most common and practical of which is tin, that, unlike stainless steel or nickel, is readily refurbish able.
It's not absolutely necessary that you keep the copper bright and shiny; just keep it clean. Though commercial copper cleaners work best, you can also use a paste you can make with a little flour, salt and water. Limited amount of copper consumption is also good for health and acidic foods cooked in brass cookware mix with the brass lining making food tastier and preserving its ingredients.
